Colonic Diverticula Are Not Associated With Mucosal Inflammation or Chronic Gastrointestinal Symptoms

Abstract

Background & aims: Colonic diverticulosis has been reported to be associated with low-grade mucosal inflammation, possibly leading to chronic gastrointestinal symptoms. However, there is poor evidence for this association. We aimed to determine mucosal inflammation and whether diverticula are associated with chronic gastrointestinal symptoms. We explored whether inflammation was present among symptomatic participants with and without diverticula.

Methods: We analyzed data from a prospective study of 619 patients undergoing a screening colonoscopy from 2013 through 2015 at the University of North Carolina Hospital in Chapel Hill, North Carolina. Among our participants, 255 (41%) had colonic diverticula. Colonic mucosal biopsy specimens were analyzed for levels of interleukin 6 (IL6), IL10, and tumor necrosis factor messenger RNAs by quantitative reverse-transcriptase polymerase chain reaction, and numbers of immune cells (CD4+, CD8+, CD57+, and mast cell tryptase) by immunohistochemistry. Gastrointestinal symptoms were assessed using Rome III criteria. Proportional odds models were used to estimate odds ratios (ORs) and 95% confidence interval (CIs).

Results: After adjustment for potential confounders, there was no association between diverticulosis and tumor necrosis factor (OR, 0.85; 95% CI, 0.63-1.16), and no association with CD4+ cells (OR, 1.18; 95% CI, 0.87-1.60), CD8+ cells (OR, 0.97; 95% CI, 0.71-1.32), or CD57+ cells (OR, 0.80; 95% CI, 0.59-1.09). Compared with controls without diverticulosis, biopsy specimens from individuals with diverticulosis were less likely to express the inflammatory cytokine IL6 (OR, 0.59; 95% CI, 0.36-0.96). There was no association between diverticulosis and irritable bowel syndrome (OR, 0.53; 95% CI, 0.26-1.05) or chronic abdominal pain (OR, 0.68; 95% CI, 0.38-1.23). There was no evidence for inflammation in patients with symptoms when patients with vs without diverticulosis were compared.

Conclusions: We found no evidence that colonic diverticulosis is associated with mucosal inflammation or gastrointestinal symptoms. Among patients with symptoms and diverticula, we found no mucosal inflammation.

Keywords: Irritable Bowel Syndrome; Painful Diverticular Disease; Symptomatic Diverticulosis; Symptomatic Uncomplicated Diverticular Disease.